contact: improve default contact picture

Change-Id: I02aaa6715995e2344a9227c2e3c3f70b74f5101f
diff --git a/ring-android/app/src/main/res/layout/item_account.xml b/ring-android/app/src/main/res/layout/item_account.xml
index 3960d91..5daec42 100644
--- a/ring-android/app/src/main/res/layout/item_account.xml
+++ b/ring-android/app/src/main/res/layout/item_account.xml
@@ -31,7 +31,7 @@
         android:layout_height="40dp"
         android:layout_centerVertical="true"
         android:layout_marginEnd="16dp"
-        tools:src="@drawable/ic_contact_picture" />
+        tools:src="@drawable/ic_contact_picture_fallback" />
 
     <TextView
         android:id="@+id/account_alias"